Abstract: An air flow rate control device for a rotating or stationary vane throat in a bowl mill pulverizer. The air flow rate control device comprises an adjustable deflector mounted on the lower surfaces of the pitched vanes to provide varying air flow passage cross sections. In one embodiment the deflector comprises a flexible member whose shape can be varied using manual adjustment apparatus to alter the air flow passage cross-section.

Abstract: Vibration in the operation of a rolling mill is minimized by mixing unground raw material with partially ground material being recirculated in such a manner that the material fed to the bowl of the mill is homogeneously mixed whereby variations in the frictional forces within the bowl will be reduced. If necessary, the moisture content of the mixture being fed into the mill bowl may be increased to ensure that the grinding operation is performed efficiently.

Abstract: The compound grinding apparatus comprises a roller mill and rollers, installed in one body and fixed in such a way that they can be rotated relative their own axes of symmetry which are above a slewing table with a rotation drive and a rotating air separator fixed above the roller mill and made in the form of a screened rotor installed inside an impingement ring and equipped with a controlled rotation drive, the unique feature of which is that with the aim of specific power consumption reduction for required grinding degree, capacity increase and improvement of grinding quality it is equipped with a jet grinder with the material circulation units and feed pipelines which end in nozzles elements connected with a pressure source, the jet grinder being mounted between the roller mill and the air separator inside the same body.

Abstract: An improved rotating throat/air port ring assembly is described for use in a pulverizing mill of the type including a rotating bowl member in a housing. The improved assembly includes (1) a vaned throat/air port ring element secured to the periphery of the bowl and including vanes which are tilted 20.degree. to 40.degree. from vertical, (2) an inclined liner extending around the bowl above the ring element, and (3) a skirt extending outwardly and downwardly from the ring element to guide inlet air through the vaned throat/air port ring element.

Abstract: The invention relates to a dynamic roller mill air classifier, which is provided in integrated manner over a roller mill. As existing air classifiers suffered from certain disadvantages with respect to the specific energy requirement, the invention makes it possible to reduce the latter. The air classifier is designed as a downflow classifier, which classifies in an efficient manner with reduced flow rates.

Abstract: An air flow rate control device for a rotating or stationary vane throat in a bowl mill pulverizer. The air flow rate control device comprises an adjustable deflector mounted on the lower surfaces of the pitched vanes to provide varying air flow passage cross sections.

Abstract: A grinding mill comprising a mill cylinder, a vertically mounted main shaft coupled at the lower end to a motor mounted on the lower side of the mill cylinder to be driven thereby and extending along the axis of the mill cylinder, and means mounted in descending order on the main shaft including a finished product conveying means, a classifying means, a grinding roller means and a decelerating means, a fixed sleeve fixed on the bottom of the mill cylinder to support a rotary bushing by means of bearings, a circular seat portion and a support seat fixed to the upper end of the rotary bushing, wherein the support seat is fixed with a grinding ring, a plurality of grinding rollers are rotatably provided inward of the grinding ring, a clearance is formed between the grinding ring and the grinding rollers, wherein a plurality of radially extended sweeping sheets are provided outside of the circular seat portion for sweeping the material fallen upon it away from the mill, and wherein an air inlet duct is provided a

Abstract: A coal pulverizer, that supplies a coal-in-air mixture to combustion means for a power plant and comprises grinding means consisting of wheels revolving in a power driven trough from which pulverized coal is centrifugally thrust into a stream of forced air blown upward through air passages in a throat ring consisting of uniformly sized segments, is provided with a wear ring of uniformly sized segments resting flush on the throat ring segments of equal arcuate dimension. Each said wear ring has a substantially trapezoidal cross section, the base of which rests on a throat ring segment, the vertical face of which fits against the inner wall of the pulverizer and the sloping face of which rises upward from its base at an angle measured from the vertical of between ten and seventeen degrees for approximately 21/2 and 31/2 inches, so as to deflect the coal-air stream away from direct impingement on the pulverizer housing.

Abstract: An apparatus and method for monitoring and controlling the flow of fluid transported solid particles is described. Also an integrated system is disclosed for monitoring and controlling pulverized coal in a non-intrusive manner employing a fluid such as air. The coal flow in each feed pipe is regulated so as to achieve a desired flow balance among the burners in a boiler.

Abstract: A pulverizer for particulate material such as coal includes a housing having a centrally located feed chute, and enclosing a rotary grinding table having an air port unit formed as multiple segments removable attached to the rotary table outer periphery and containing air flow passageways. Located adjacent the air port unit is an outer segmented ring attached rigidly to the pulverizer housing, with a radial gap being provided between the outer ring and the air port unit ring segments. The outer ring segments include upper wear plugs removably attached onto the outer ring lower segments. Whenever the upper parts of the air port unit segments become worn excessively due to erosion, or there is a need to change air flow requirements of the pulverizer, the rotatable air port segmented ring upper parts only are conveniently replaced along with the upper wear segments of the adjacent outer stationary ring.

Abstract: The invention relates to apparatus for delivering material to part of a plant, for example to a crushing and grinding machine, in which the fines are separated out of the feed material passing through the material feed chamber by means of an air stream. In this way a substantial increase in the output of the part of the plant can be achieved.

Abstract: There is disclosed a vertical mill comprising a rotatable table and rotatable grinding rollers disposed on the upper surface of the table near the outer periphery of the table. Raw material is supplied to the central portion of the table. A given grinding pressure is applied to each grinding roller to crush the raw material between the upper surface of the table and the outer surface of each grinding roller. Rotatable auxiliary rollers are arranged alternately with the grinding rollers on the upper surface of the table near the outer periphery of the table. The layer of the material caught by the grinding rollers are compacted by the outer surfaces of the auxiliary rollers. There is also disclosed a method of operating the vertical mill. The method consists in separating controlling the grinding pressures applied to the grinding rollers according to the loads on the grinding rollers.

Abstract: Accommodated inside the housing (1) of a bowl-and-roller mill is a rotating grinding bowl (3) with segments (7) that stationary rollers (8) roll over. Blades (20) are cast onto the outside circumference of a nozzle ring (15).

Abstract: An apparatus for supplying a controlled flow of pneumatically transported solid particles, in particular, pulverized coal, comprises a pulverizer or vessel for containing pneumatically suspended solid particles. A supply pipe is connected to the pulverizer or vessel for removing a mixture of pneumatic gas and solid particles from the vessel. A bend is provided in the supply pipe and an aspirator is connected to the supply pipe at a distance of from one to two pipe diameters from the bend. The aspirator is provided on the outer wall of the bend and is supplied with aspirating gas to draw off an amount of mixture from the supply pipe. This controls the amount of remaining flow of mixture through the pipe. The supply of the aspirator is connected to a bypass line which is connected to the mixture inlet of an injector which is supplied with injecting gas. The supply of the injector which carries the mixture is connected back into the vessel.

Abstract: The invention relates to a grinding process and apparatus for the simultaneous production of at least two finished products of differing fineness using a ring mill. Pre-classification is carried out in the nozzle ring by adjusting the air to entrain and carry upwards relatively fine constituents. The coarser constituents are discharged downwardly by gravity and subsequently may be conveyed upwards by an elevator and subjected to a second classification in which at least a proportion is extracted as finished product.

Abstract: The invention relates to a roller mill with a mill casing having a vertical axis, a grinding table rotating therein about the casing axis and two grinding rollers which roll on the grinding table and are held stationary by a roller carrier. This roller mill is intended in particular for small throughput capacities, and both grinding rollers are rigidly connected by their spindles to one another and to the roller carrier which passes diametrically through the mill casing and is flexibly and resiliently mounted or supported at its ends. In this way a simple and robust, reliable construction is produced.

Abstract: A rotating throat pulverizing mill has a soft steel vane wheel which rotates with the control bowl for classifying purposes. Wear-resistant vane liners slide onto the vanes to protect the upper surfaces thereof and are held in place, in part, by integral clips which underlie the vane plates and, in part, by wear-resistant cap plates which are welded to a flush upper flange of the vane wheel. Arcuate wear plates are also welded to the exposed surfaces of an air deflector outboard of and above the vane wheel. The vane wheel is preferably constructed in segments. A modified deflector assembly comprises a first portion having a base plate and spaced vertical ribs, which first portion is bolted to a lower deflector, and a box-like, wear-resistant cover assembly which seats on the ribs and is welded to the seat blocks by ways of access holes.

Abstract: An apparatus and method for supplying a controlled flow of fluid transported solid particles, in particular, pulverized coal by the controlled injection of a fluid, such as a gas like compressed air, into at least one feed pipe. The flow of coal in feed pipes is controlled by selectively reducing or increasing the flow of primary air to achieve a balanced burner operation.

Abstract: In the vertically oriented generally cylindrical coal pulverizers that are widely employed to supply a coal-air dispersion to the combustion zones of boilers producing steam for the turbines of electric-power plants, forced-air requirements are reduced and coal fall-back and resultant coal fires are substantially eliminated by the novel throat ring of invention. A throat ring surrounds circumferentially the coal grinding assembly of each such pulverizer and contains a plurality of angularly disposed air channels through which air is forced upwardly into contact with pulverized coal thrust centrifugally from the said assembly causing the coal-air mixture to swirl upwardly to means directing the mixture to the said combustion zones.

Abstract: A vertical roller mill has a rotatable grinding table (1) which is fed with material to be ground through a feed pipe (14) so that a cone of material is formed between the bottom of the pipe and the table, and scrapers (25) for intercepting the cone and spreading the material over the table and under grinding rollers. In order to avoid the feed pipe running empty so that the cone is not formed, sensors (21) sense the level of material in the pipe and controlling means (19,20) responsive to the sensors adjust the height of the feed pipe and/or the angle of the scrapers.

Abstract: An apparatus for supplying a controlled flow of pneumatically transported solid particles, in particular, pulverized coal, comprises a pulverizer or vessel for containing pneumatically suspended solid particles. A supply pipe is connected to the pulverizer or vessel for removing a mixture of pneumatic gas and solid particles from the vessel. A bend is provided in the supply pipe and an aspirator is connected to the supply pipe at a distance of from one to two pipe diameters from the bend. The aspirator is provided on the outer wall of the bend and is supplied with aspirating gas to draw off an amount of mixture from the supply pipe. This controls the amount of remaining flow of mixture through the pipe. The supply of the aspirator is connected to a bypass line which is connected to the mixture inlet of an injector which is supplied with injecting gas. The supply of the injector which carries the mixture is connected back into the vessel.

Abstract: The apparatus operates to supply the air requirements for grinding a fuel material to the mill to guarantee the correct particle size and to decouple from the air emitted from the grinding apparatus a certain proportion so the combustion of the ground fuel material will be conducted at a ratio of less than the usual 3 to 1 ratio of air-to-fuel so the combustion can be controlled to reduce the nitrous oxide emission, the air that is decoupled is returned to the grinding apparatus with a supply of make up air that is heated for purposes of drying the material in the grinding apparatus.

Abstract: A pulverizing mill (10) wherein the pulverized material is classified by a vertical separator (38) as the pulverized material exits the pulverizing mill thus permitting the height of the mill to be reduced.

Abstract: A method of controlling a bowl-mill crusher that has cylinders that remain in one position and roll over a rotating bowl with a predetermined force. Raw coal and primary air are supplied to the crusher and the crushed coal is removed from the crusher along with the primary air through a separator and supplied to burners through a pulverized-coal line. The pressure of the primary air where it enters the bowl-mill crusher is controlled in accordance with load and in a manner so that the pressure of the crushing cylinders against the bowl is decreased in a predetermined manner when the desired load-dependent level is not attained and is increased when the level is exceeded.

Abstract: An apparatus for treating a particulate material comprising a casing defining a treating chamber and rotatable at high speed to produce a centrifugal force for pressing the material in the casing against an inside wall surface of the casing. Treating members such as pulverizing members are disposed in the casing for revolution relative to the inside wall surface of the casing. The treating chamber has a discharge opening for permitting overflows of the material under treatment. The discharge opening is disposed adjacent a center of rotation of the casing, and a limiting device is provided adjacent the discharge opening for limiting the overflows of the material under treatment. A classifier is provided to communicate with the discharge opening of the treating chamber for receiving treated material.

Abstract: An orifice assembly (6) used in a pulverized coal supply line (4) is formed of a plurality of ceramic bull nose inserts (20). Each insert is of truncated pie shape and of sufficient number around the periphery to radially lock the inserts.

Abstract: A vane wheel assembly (12) particularly suited for use in a mill (10) so as to be operative to effect a primary classification of the material such as coal that is subjected to pulverization within the mill (10). The subject vane wheel assembly (12) includes a first channel-like means (40) mounted in supported relation on the bowl (16) of the mill (10) for rotation therewith and so as to lie in a first plane which extends in a first direction. The subject vane wheel assembly (12) further includes a second channel-like means (42) mounted in fixed relation on the interior of the millside area (15) of the mill (10) at the exit end of the first channel-like means (40) so as to extend a full 360.degree. around the circumference of the millside area and so as to lie in a second plane that extends in a second direction which is inclined at a predetermined angle to the first plane of the first channel-like means (40).

Abstract: A roll-and-race pulverizer is disclosed in which the throat vanes are mounted for rotation in the direction of rotation of the grinding ring.

Abstract: A vertical roller mill has stationary grinding rollers which roll over a grinding path (4) of a rotatable grinding table (1), and a surrounding nozzle ring (7) for conveying and separating air. A coarse fraction of ground material is entrained upwards and radially inwards over an inclined outer wall (19) of a screen (15) and is directed downwards by an overlying guide wall (16) onto an inclined inner wall (20) of the screen (15) and hence back to the grinding table (1) for further grinding.

Abstract: The invention relates to a roller mill with a sifter arranged above it which is provided with a deflecting rotor and an adjustable ring of guide vanes. Such a construction is distinguished by a particularly high degree of separation.

Abstract: A separator for sorting particulate material has a rotor (1) with vanes (3); static, separately adjustable guide vanes (8,9); a casing (14) defining an inlet duct for material suspended in a conveying gas; an outlet (7) for a suspended fine fraction; and a hopper (12) for collecting a coarse fraction.

Abstract: A roll-and-race pulverizer is disclosed in which the throat vanes are mounted for rotation in the direction of rotation of the grinding ring.

Abstract: A vertical mill, a classifier for the mill, and a controller for the classifier. The vertical mill includes a casing having a top plate, and the classifier is adjacent the top plate. Beneath the top plate, upon which impinges an upwardly moving gas and powdery material being supplied from the lower portion of the casing, are provided a plurality of rotary blades or rotary rods which have a vertical axis of rotation. A gap is provided between the rotary blades and the top plate, and an annular impingement member is suspended from the top of the casing to outwardly surround the plurality of rotary blades in such a way as to shield the gap. Further, an opening is provided adjacent the impingement member through which a portion of the gas and powdery material pass. The controller of the classifier includes means for adjusting the opening through which the powdery material passes.

Abstract: Centrifugal air classifiers without rotating classifying blades are frequently used in present-day coal-fired power stations. For economical reasons, these obtain the coal to be burnt from different sources so that the pulverized-coal furnaces are operated with coals of varying quality. In this arrangement, it is disadvantageous that, when coals of particularly low quality are burnt, this classifier is not capable of supplying the fineness of pulverized coal required for proper combustion. The invention has the object of creating a centrifugal air classifier of the type initially mentioned which provides the possibility of proper combustion of several types of coal in a pulverized-coal furnace.

Abstract: A control system (44, 112) particularly adapted to be cooperatively associated with a mill (10) and in particular a roller mill (10) of the type that is operative to effectuate the grinding and/or pulverization of solid materials. When so employed, the subject control system (44, 112) enables the roller mill (10) to be operated over a wide range of varying levels of output of pulverized material, while yet ensuring that both the proper air/solids ratio and the desired degree of fineness of the pulverized material are being maintained. To achieve this result, the subject control system (44, 112) is operatively connected in circuit relation with the feed means (12) that supplies to the roller mill (10) the material that is to be pulverized therein, with the drive means (20, 22) through which the mill (10) is driven, with the classifier means (38) that effects a separation of the pulverized material according to fineness, and with the means which receives the output from the roller mill (10).

Abstract: A vane wheel arrangement (30) particularly suited for use in a bowl mill (10) of the type that is employed for purposes of effecting therewithin the pulverization of materials such as coal. The subject vane wheel arrangement (30) which is positioned within the bowl mill (10) so as to be located in the path of flow of the air that in flowing through the bowl mill (10) transports therewith the pulverized material, is operative to effect a primary classification of the pulverized material. Encompassed within the subject vane wheel arrangement (30) are vane means (36) supported on the rotatable grinding surface (14) of the bowl mill (10) for rotation therewith, and a converging/diverging orifice means (38) located in spaced relation to the rotatable grinding surface (14). Both the vane means (36) and the exposed surfaces of the converging/diverging orifice means (38) are formed of a material that is noted for its good abrasive resistant qualities.

Abstract: A vane wheel arrangement (30) particularly suited for use in a bowl mill (10) of the type that is employed for purposes of effecting therewithin the pulverization of materials such as coal. The subject vane wheel arrangement (30) which is positioned within the bowl mill (10) so as to be located in the path of flow of the air that in flowing through the bowl mill (10) transports therewith the pulverized material, is operative to effect a primary classification of the pulverized material. Encompassed within the subject vane wheel arrangement (30) are vane means (36) supported on the rotatable grinding surface (14) of the bowl mill (10) for rotation therewith, and a converging/diverging orifice means (38) located in spaced relation to the rotatable grinding surface (14). Both the vane means (36) and the exposed surfaces of the converging/diverging orifice means (38) are formed of a material that is noted for its good abrasive resistant qualities.

Abstract: A bowl mill has a vertical mechanism to drive a milling bowl and a hot-air supply to an air box positioned below the bowl. An evacuator is positioned in the air box to prevent the box from overflowing when the mill shuts down suddenly. The evacuator has a drive mechanism that is separate from and independent of the mechanism that drives the mill.

Abstract: The invention relates to grinding apparatus and a method of operating such apparatus in which the gas speed in the nozzle ring of the mill is altered as a function of the power consumption of the bucket conveyor so that the quantity of material conveyed by the bucket conveyor and the gradation of grain sizes thereof are kept constant. A control circuit alters the material supply to the mill when the gas speed in the nozzle ring exceeds a predetermined maximum value or falls below a predetermined minimum value.

Abstract: A vertical mill for material such as cement raw materials, clinker, coal, or the like comprises a grinder portion which has rollers arranged to grind the material by their rolling on a rotary table, a separator means which is positioned above the grinder portion and which classifies the ground material conveyed pneumatically from the grinder portion to the separator means by the two opposite forces of centrifugal force of a rotary disk and of fluid resistance of a vortex flow, a plurality of straightening vanes which are mounted between the casing and the inner cone and which adequately regulate the direction of the fluid in the lower portion and in the upper portion in passage between the grinding portion and the separator means, and a casing outside the separator means having the appropriate shape for forming a horizontal vortex flow in the separator means. The aforesaid vertical mill structure improves the classifying efficiency of the separator means.

Abstract: A vertical roller mill has a grinding table (1), rollers (3) and a separator (6) for separating ground material, which is conveyed to the separator in an air stream supplied through an inlet (7), into a fine fraction, which passes out through an outlet (8), and a coarse fraction which is returned for further grinding through an outlet (10). A part of the ground material is conveyed through an outlet (11) to a second separator (13), where it is separated from the air and returned for further grinding via an outlet (14) and an inlet (9) for fresh material to the mill. This provides a flatter grain size distribution curve in the finish ground material.

Abstract: An improved milling process, wherein the material to be crushed is processed within a circular milling path under the action of at least one roller rolling along said path. The material is fed evenly distributed around the circumference of the milling path and enters it with a predetermined initial speed transversely to the extension of the path such that each piece to be crushed is subjected at least once to the action of one of the rollers. Under the action of an air current which is guided across the milling path pulverized material below a given grain size is immediately removed from the milling path, thereby avoiding the build-up of a thick and energy consuming layer on the milling path such that the milling forces are limited to the breaking forces for crushing the pieces fed into the milling path.

Abstract: There is disclosed a grinding crusher having a grinder piece disposed within a crushing chamber for relative rotation with respect to a casing defining the crushing chamber. The casing is journaled and driven in high speed rotation so as to cause a material within the casing to be centrifugally pressed against the inner peripheral surfaces thereof.

Abstract: A vane wheel arrangement (30) particularly suited for use in a bowl mill (10) of the type that is employed for purposes of effecting therewithin the pulverization of materials such as coal. The subject vane wheel arrangement (30) which is positioned within the bowl mill (10) so as to be located in the path of flow of the air that in flowing through the bowl mill (10) transports therewith the pulverized material, is operative to effect a primary classification of the pulverized material. Encompassed within the subject vane wheel arrangement (30) are vanes (36) supported on the rotatable grinding surface (14) of the bowl mill (10) for rotation therewith, and a converging/diverging orifice (38) located in spaced relation to the rotatable grinding surface (14). Both the vanes (36) and the exposed surfaces of the converging/diverging orifice (38) are formed of a material that is noted for its good abrasive resistant qualities.

Abstract: A system for pulverizing coal to be burned in a furnace (20), where nearly all of the coarse ash particles are removed from the coal prior to its introduction to the furnace. The system includes a pulverizing mill (10) having a first classifier (12) in its outlet for separating some of the large, heavy particles and returning them to the pulverizer. A second classifier (16) is connected to the first classifier, and includes a curved duct (16) wherein the solid particles being carried in an airstream are thrown outwardly against an outer wall. A skimmer blade (78) extending through the outer wall skims off a percentage of the large, heavy particles, the percentage depending on how much coarse ash the coal stream contains. The rest of the coal particles are conveyed to a furnace and burned therein. The separated large, heavy particles are passed through an ionizer (30) and then through an electrostatic separator (34), where the inorganic particles are separated from the coal particles.

Abstract: A vertical roller mill has a rotary grinding table (1), grinding rollers (3) and a nozzle ring (13) surrounding the table for providing an air stream to entrain ground material. Downstream of each roller is a scraper (20) with a nozzle for directing a blast of air onto the crushed material leaving the roller to break up the material so that finer fractions pass into the conveying air stream and coarser fractions are carried on the table to the next roller.

Abstract: A new and improved design of a pulverizer air throat for low-pressure drop, reduced erosion and improved flow distribution.

Abstract: An improved pulverizer roller loading arrangement applying compressive force directly to roller brackets and providing shear and pivoting means integrally connecting roller brackets to split corner roller support blocks.

Abstract: A pulverizing bowl mill embodying improved air deflector means and particularly suited for use in effecting the grinding of material. The subject bowl mill includes a substantially closed separator body in which a grinding table is supported for rotation. A plurality of grinding rolls are supported within the separator body and cooperate with the rotating grinding table to effect the grinding of the material, which is disposed upon the grinding table. Air deflector means corresponding in number to the number of grinding rolls are mounted within the separator body so as to be located in juxtaposed relation to the inner surface of the separator body and so that an air deflector means is interposed between each pair of adjacent grinding rolls. An air supply means suitably formed in the separator body is associated with each of the air deflector means. Each of the air supply means is operable to supply air from an external source thereof therethrough to the interior of the separator body.

Abstract: A press roll for acting in opposition to a counter roll. The press roll has a support member which is supported at its opposite ends. The support member is stationary in certain most embodiments and rotatable in one embodiment. A flexible, liquid-tight endless press jacket is wrapped around the support member. At each lateral end of the press roll, the press jacket is fastened to the outward end of a supporting disk, which is rotatably mounted on the support member. The lateral edge zones of the press jacket are both deformed radially inwardly around the outside of the respective supporting disks and each edge zone is clamped there by a annular clamping flange. To facilitate deformation of the edge zones, at least one of the edge zones terminates in a series of tongues separated by cutouts arrayed around the roll. Coiled tension springs engage the edge zone and/or the tongues to pull them in the direction toward the axis of the roll.